Survey: Correct wind rose angle

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

src/PlanView/SurveyItemEditor.qml

@@ -737,7 +737,7 @@ Rectangle {
                 var angle = Math.round(Math.atan2(point.y, point.x) * 180 / Math.PI)
                 windRoseCanvas.requestPaint()
                 windRosePie.angle = angle
-                gridAngleText.text = - angle
+                gridAngleText.text = angle
                 gridAngleText.editingFinished();
             }
         }